Grant: Operating Grant: Mechanisms in Brain Aging and Dementia

Carrying excess body weight, especially around the belly ("visceral fat") and having unhealthy lifestyles may impair a person's thinking ability including memory and multitasking. This brain fog can lead to the more serious and progressive condition known as dementia. In 2013, we assembled a cohort of over 8,000 Canadian adults from 5 provinces in a study called the Canadian Alliance for Healthy Hearts and Minds. Participants provided blood samples and underwent a magnetic resonance imaging (MRI) scan of the brain, heart, and abdomen for fat tissue at baseline. We asked them questions about their general health, diet, and exercise habits; and administered tests of their memory and thinking ability. In this study, we have recently published an analysis which shows excess fat impairs thinking ability. We now propose to recontact them and re-assess their thinking ability at 6-year follow-up. We will also invite some participants with cognitive dysfunction and others without, for further testing including assessing their food intake, physical activity, body fat (including belly fat), and another MRI scan of the brain. Using their blood samples collected at baseline, we will also measure hundreds of blood biomarkers, as markers of body fat and its metabolic activity, and test if these biomarkers can predict participants' cognition ability. This study will allow us to better understand the pathways linking lifestyles, to excess body fat, to dementia. Novel identified biomarkers could also form the basis of new clinical programs for dementia, targeting entirely new classes of therapeutics.